Yarn Weight Guide: From Cobweb to Super Bulky
Many of you who are new to crafting might be wondering — what exactly does "DK" or "worsted" mean on a yarn label? Yarn weight refers to the thickness of the yarn strand, and it determines what needle or hook size you'll use, how your finished fabric feels, and how much yarn you'll need for a project. Here's every weight category explained in plain terms, going from thinnest to thickest.
Cobweb
The finest yarn weight available — even thinner than lace. Cobweb yarn creates extremely delicate, almost transparent fabric. It's used for ultra-fine lacework, wedding ring shawls (so delicate they can pass through a ring), and heirloom pieces. Cobweb isn't part of the official yarn weight numbering system but it's widely recognized by knitters and indie dyers, sometimes grouped under Category 0 (lace). Note that crochet thread, while similar in thinness, is a different product with its own sizing system where higher numbers mean thinner thread. Working with cobweb requires experience and patience — but the results are breathtaking.
Find cobweb weight yarn on SkeinScout →Lace (Category 0)
Lace is the thinnest yarn weight category. It produces delicate, airy fabric perfect for shawls, doilies, and lightweight wraps. This category also includes crochet thread, which uses a separate numbering system (size 3 through 100, with higher numbers being thinner). It typically knits at 33-40 stitches per 4 inches on tiny needles (US 000-1 / 1.5-2.25mm). These projects take patience but the results are stunning. Because the yarn is so fine, a single skein goes a long way in terms of yardage.
Find lace weight yarn on SkeinScout →Fingering / Super Fine (Category 1)
Fingering is the most popular weight among indie dyers and hand-dyed yarn lovers. Fingering weight is the go-to for socks, lightweight shawls, and detailed color work where you want stitch definition. Gauge runs 27-32 stitches per 4 inches on US 1-3 needles (2.25-3.25mm). You'll also hear it called "sock yarn" or "4-ply." A typical 100g skein gives you around 400 yards — enough for a pair of socks or a small shawl.
Find fingering weight yarn on SkeinScout →Sport (Category 2)
Slightly thicker than fingering but lighter than DK. Sport weight is versatile — great for baby garments, lightweight sweaters, and accessories. Gauge sits at 23-26 stitches per 4 inches on US 3-5 needles (3.25-3.75mm). It's sometimes called "5-ply." Sport weight doesn't get as much love as fingering or worsted, but it hits a sweet spot between detail and speed.
Find sport weight yarn on SkeinScout →DK / Light Worsted (Category 3)
DK stands for "double knitting" — a British term that stuck around globally. It's one of the most versatile weights, suitable for sweaters, hats, baby items, and blankets. Gauge runs 21-24 stitches per 4 inches on US 5-7 needles (3.75-4.5mm). DK is also called "8-ply" in Australian and New Zealand terminology. It works up faster than fingering but still gives good stitch definition.
Find dk weight yarn on SkeinScout →Worsted / Medium (Category 4)
The most widely used yarn weight worldwide. If a pattern doesn't specify a weight, it's probably worsted. Perfect for blankets, scarves, hats, sweaters — basically everything. Gauge runs 16-20 stitches per 4 inches on US 7-9 needles (4.5-5.5mm). Also called '10-ply.' Sometimes grouped with aran, though aran is slightly heavier — see the next section. Worsted is the best starting point for beginners because it's easy to handle and widely available.
Find worsted weight yarn on SkeinScout →Aran
Sits between worsted and bulky. Aran weight gets its name from the Aran Islands off the coast of Ireland, known for their heavily textured cable-knit sweaters. That's still what it's best known for — cables, textured stitches, and structured garments that need a bit more heft than worsted. Gauge runs around 16-18 stitches per 4 inches on US 8-9 needles (5-5.5mm). Aran is sometimes grouped with worsted under Category 4, but in practice it knits up noticeably thicker.
Find aran weight yarn on SkeinScout →Bulky / Chunky (Category 5)
Thick yarn that works up fast. Bulky weight is ideal for cozy winter hats, cowls, thick scarves, and quick blankets. Gauge runs 12-15 stitches per 4 inches on US 9-11 needles (5.5-8mm). Projects in bulky yarn feel rewarding because you see progress quickly. The tradeoff is that the finished fabric is heavier and uses more yarn by weight for the same area.
Find bulky weight yarn on SkeinScout →Super Bulky (Category 6)
Even thicker than bulky. Super bulky yarn creates very chunky, warm fabric. Think oversized cowls, quick-knit blankets, and statement accessories. Gauge runs 7-11 stitches per 4 inches on US 11-17 needles (8-12.75mm). A hat in super bulky yarn can be finished in an evening.
Find super bulky weight yarn on SkeinScout →Quick Reference
| Weight | Category | Stitches per 4" (knit) | Needle size (US) | Common names |
|---|---|---|---|---|
| Cobweb | — | varies | varies | Cobweb, gossamer |
| Lace | 0 | 33-40 | 000-1 | Lace, thread |
| Fingering | 1 | 27-32 | 1-3 | Sock, 4-ply, baby |
| Sport | 2 | 23-26 | 3-5 | 5-ply |
| DK | 3 | 21-24 | 5-7 | 8-ply, light worsted |
| Worsted | 4 | 16-20 | 7-9 | 10-ply, afghan |
| Aran | — | 16-18 | 8-9 | Irish aran |
| Bulky | 5 | 12-15 | 9-11 | Chunky, craft, rug |
| Super Bulky | 6 | 7-11 | 11-17 | Roving |
Note: Gauge ranges are guidelines based on industry standards from the Craft Yarn Council. Your actual gauge depends on your tension, needle material, and yarn fiber.
Frequently Asked Questions
What is DK weight yarn?
DK (double knitting) is a medium-light yarn weight, Category 3 on the standard numbering system. It knits at 21-24 stitches per 4 inches on US 5-7 (3.75-4.5mm) needles and is popular for sweaters, hats, baby items, and blankets — it works up faster than fingering while still holding good stitch definition.
What is the difference between worsted and aran?
Worsted (Category 4) is the most widely used yarn weight, knitting at 16-20 stitches per 4 inches on US 7-9 needles. Aran sits just above it — around 16-18 stitches per 4 inches on US 8-9 needles — and is traditionally used for heavily textured cable-knit sweaters. The two are sometimes grouped together, but aran knits up noticeably thicker than worsted.
What is cobweb weight yarn?
Cobweb is the finest yarn weight available, even thinner than lace. It isn't part of the official numbering system, but it's widely recognized by knitters and indie dyers for ultra-fine lacework, wedding ring shawls, and heirloom pieces.
What is the difference between yarn weight and crochet thread size?
They're two different sizing systems. Yarn weight runs from cobweb (finest) to super bulky (thickest) and covers standard knitting and crochet yarns. Crochet thread is a separate product — typically mercerized cotton with a tight twist, used for doilies, lace trims, and fine detailed work. It's sized 3 through 100, where higher numbers mean thinner thread — the opposite direction from yarn weight categories. Crochet thread is sometimes grouped with lace weight since both are very fine, but they use distinct sizing conventions.
Not sure which weight is right for your project? Search on SkeinScout and use the weight filter to explore yarns in any category across hundreds of indie dyers.